Lactobacillus rhamnosus GG supplementation for preventing respiratory infections in children: a meta-analysis of randomized, placebo-controlled trials.

OBJECTIVE To systematically review the effectiveness of administering Lactobacillus rhamnosus GG (LGG) for preventing respiratory infections in children. DESIGN Systematic Review and Meta-analysis. DATA SOURCES Electronic databases and trial registries. RESULTS Four RCTs involving 1805 participants met the inclusion criteria. Compared with placebo, LGG administration was associated with a reduced incidence of acute otitis media (four RCTs, n=1805, RR 0.76, 95% CI 0.64-0.91, fixed effects model, NNT 17, 95% CI 11-46), a reduced risk of upper respiratory infections (one RCT, n=281, RR 0.62, 95% CI 0.50-0.78, NNT 4, 95% CI 3-8) and antibiotic treatments (four RCTs, n=1805, RR 0.80, 95% CI 0.71-0.91, fixed effects model). There was no significant difference between the LGG and the control groups in the risk of overall respiratory infections and the incidence of lower respiratory infections. However, subgroup analysis of two studies on children older than 1 year showed significant reduction in the risk of overall respiratory infections (two RCTs, n=794, RR 0.73, 95% CI 0.57-0.92, random effects model, NNT 8, 95% CI 5-14). Adverse effects were similar in both groups. No serious adverse events were reported. CONCLUSION The administration of Lactobacillus rhamnosus GG compared with placebo has the potential to reduce the incidence of acute otitis media, the upper respiratory infections and antibiotic use in children.